Leakproof carton



Aug. 15, 1944.

W. H. INMAN LEAK-PROOF CARTON Filed May 6, 1943 2 Sheets-Sheet 1 INYENTOR. WZ'ZZL a/n fl [1% 115 142 Zorue 5 Aug. 15, 1944. w. H. INMAN LEAK-PROOF CARTON Filed May 6, 1943 2 Sheets-Sheet 2 INVENTOR.

Wf -%z:5 A

Patented Aug. 15, 1944 LEAKPROOF CARTON William H. Inman, Newark, N. Y assigrior to Bloomer Bros. Company, Newark, N. Y., a corporation of New York Application May 6, 1943, Serial No. 485,869

2 Claims. (Cl. 229-26) This invention relates to containers, or cartons, made of cardboard, or other foldable sheet material, cut, scored, folded and fastened to form a set-up, leak-proof carton, such, for example,

as the tapered cardboard pails commonly employed for holding liquid or semi-liquid food materials, one object of the invention being to provide a more eflicient carton of the character described having closure locking means and handie means produced integrally and economically from the sheet material itself, without separately formed attachments of metal or other materials.

Another object is to provide a carton of the above character having a relativelyliquid-tight body and closure construction, with strong, integral handle means so arranged as to avoid the application of any deranging force to the closure parts.

Another object is to provide such a carton having closure locking means capable of being readily, rapidly, and securely engaged by unskilled operators, so as to hold the top tightly closed against leakage of liquid contents.

Another object is the provision of such a carton having handle means integrally connected to the carton by a resilient type of construction adapted to safely absorb jars and shocks in supporting and carrying the carton and so arranged that the weight of the carton is transmitted to the handles as stresses of the substantially tensile type which the handle material is well adapted to sustain.

Another object is the provision of a leakproof pail of the character described having reinforced opposite side walls and outer top closure flaps connected with such side walls and arranged to provide strong closure locking and handle parts.

Another object is to provide a leak-proof pail of the nature described having adjacent sides integrally connected by corner folds secured to opposite side walls, to reinforce the same, and liquid-tight top closure flaps adapted to further reinforce said ,side walls both when folded outand scored for folding to form a container embodying the present invention;

Fig. 2 is a perspective view of the container after folding and gluing, but with its top open;

Fig. 3 is a similar view, but showing the container with its top closed ready for transportation;

Fig. 4 is a reduced side elevation of the same;

Fig. 5 is an enlarged, sectional view on the line Uzi-5a in Fig. 4;

Fig. 6 is an enlarged view similar to Fig. 4, but showing the closure locking sections disposed in position for engagement with each other;

Fig. 7 is a plan view on the line lala in Fig. 6;

Fig. 8 is a view similar to Fig. 6, but showing the locking means after engagement;

Fig. 9 is a plan view on the line-Sa-Sa in Fig. 8, and s Fig. 10 is a view showing the locking means and handles in transporting position as in Fig. 4, but on a larger scale.

The invention is embodied in the present instance. by way of illustration, in a container, or carton, of the variety made from a sheet of cardboard cut, scored, folded and glued to form a tapered, leak-proof "paiP with integral closure and handle means. The cut and scored cardboard blank for forming the pail is shown in Fig. 1, comprising score lines I0, ll, l2, and I3, bounding a rectangular bottom portion i4.

Score lines. I! to 22, inclusive, project radially from the comers of the bottom, as shown, to separate four tapered side walls, 23 to 26, inclusive. The pairs of adjacent side walls are connected at each of the included comers by outwardly folded portions, 28 to 3|, inclusive.

Each of these portions is substantially bisected by a score line, as 21, about which each portion is folded upon itself and then folded and fastened flat against one of the side walls.

- against the outer face of side wall 24 and fixed wardly and downwardly during the filling of the pail and when folded inwardly and interlocked to close it.

To these and other ends the invention resides in certain improvements and combinations of parts, all as will be heinafter more fully described, the novel features being pointed out in the claims at the end of the specification.

In the drawings: Fig. 1 is a plan view of a cardboard blank cut thereto by an interposed glued area indicated at a 82, Fig. 1. The corner fold portion 29 is similarly folded against side wall and portion 28 and is secured to them by means of glued areas 34 and 33, respectively. Corner fold portion 30 is similarly folded and glued against side wall 28 and comer portion 30, as indicated in Fig. 5. It will thus be seen that the outwardly folded corner portions are folded and glued in overlapping pairs againstone pair of opposite side walls 24 and 26. Such a construction affords a fluidtight container, or pail, in which the edges of the blank extend to the carton top without any Joints below the top. The folded corner portions also serve to reinforce and stiffen the side walls 24 and 28.

The top closure is preferably formed in part by integral extension of the upper edges of side walls 23 and 25 to provide the inner top closure flaps 35 and 36, which are arranged to fold inwardly about score lines at the tops of the side walls, so as to close the top of the carton, as shown in Fig. 5.

The other pair of opposite side walls' 24 and 26 have their upper edges extended integrally to form outer top closure flaps, 3land 38, which are also arranged to fold inwardly about score lines at the tops of the respective side walls.

While the glue spots 32, 33 and 34 are of sumcient size to securely hold the parts in folded relation, their size and arrangement are such as to leave ample areas on the blank for the engagement thereof by feed rolls for feeding the same in each of transverse directions while the glue is being applied, without interference with the glue pads or the spots of glue applied thereby. Thus the glue spots 32 are located in the upper central portion of the opposite side walls 24 and 26 and the -'glue spots 33 and 34 are suitably arranged on the same side walls and on the opposite corner fold portions 28 and 3|, leaving the opposite corner fold portions 28 and 3|) without directly applied glue. This leaves one clear path for feed rolls diagonally through the bottom portion l4 and through the opposite corner portions 28 and 38 for feeding the blank in one direction. Similarly, the flap portions 35 and 31 and the corner portion 28 provide a path for feed rolls, outside the glue spot 32, in a direction parallel to a similar' path across the flaps 36 and 38 and the corner portion 30 outside the other glue spot 32. These spaced parallel paths provide for feeding the blank in a direction transverse to said path through the bottom portion I4 and, by means of these paths, the blank may be fed in two directions toward and from the glue applying pads, without interference therewith or the gumming of the feed rolls with glue.

Top closure flaps 3i and 38 are each provided with a score line 38 extending continuously thereacross, parallel with and at a substantial distance from the score line about which the flap is folded at the top comer of the carton. Each of the flaps is cut by a substantially U-shaped slit 40 extending outwardly-from the score line 38, as shown. Each flap is thus separated by slit 48 into an inner locking section and an outer apertured handle section. Thus the fiap 31, for example, has an inner locking section 4| and an outer handle section 42, as shown.

Section 4| has an opening 43 cut therein to form a locking eye for interlocking engagement with a complementary part on the opposite flap 38. Flap 38 is similarly cut to provide an inner locking section 44 having a hooked end portion 45 for engagement with eye 43, and an outer apertured handle section 46. The ends of eye 43 and hook 45 are bevelled for easy entrance of the hook into the eye. The extreme width of the hook and eye are substantially the same, but the oppositely projecting shoulders 41 of the hook are wider than the reduced outer side of the eye so as to interlock therewith, as further described hereafter.

It will be noted that the sides 24 and 26 of the pail are the wider sides and these sides tend to be bulged outwardly by the weight of the contents as the pail is filled, so as to somewhat increase its intended capacity. The corner folds 28 to 3|, inclusive, are therefore preferably folded against and secured to these wider sides to reinforce and stiffen the same. In filling the carton, furthermore, it is customary to turn the top closure flaps of these wider sides, as 31 and 38, downwardly against the outside of the comer folds so as to further support these wider sides against bulging, and it is one of the advantages of the present construction that the flaps 31 and 38 are not weakened by scopes or cuts for a substantial distance inwardly from the corner of the carton, thus leaving unweakened portions of the closure flaps for further stiffening the side walls 24 'and 26 in both the open and closed positions of the flaps.

In closing the carton the inner top closure flaps 35 and 36 are folded inwardly and downwardly so as to overlap and lie flat across the top opening, as shown, for example, in Fig. 6. The outer flaps 31 and 38 are then folded at the carton corners so as to extend at a substantial inclination inwardly and upwardly, as shown in-Fig.6, in which position they overlap the edges of the inner flaps and hold the same in flatly closed, leakproof position. In this position of the outer fiaps,.their score lines 38 remain at a substantial elevation above the'inner flaps, and locking section 4| is then further bent about its score line 38, so as to be inclined inwardly and downwardly, as shown in Fig. 6, with its end against the inner flaps. Locking section 44 is then bent inwardly and downwardly in a similar way about its score line 38, so as to extend in intersecting or crossing relation with the opposite locking section 4| and in these relative positions, the hook 45 may be readily and rapidly inserted into the eye 43, as shown in Figs. 6 and 7. Flaps 31 and 38 are then pushed further inwardly and downwardly, which thrusts the hook fully through the eye, as shown in Figs. 8 and 9, and when the flaps are released and spring upwardly, as shown in Fig. 10, the overhanging shoulders 41 of the hook engage and interlock beneath the bevelled ends 48 of the eye, and any further pull on the locking sections tends to increase their interlocking engagement.

When the carton is thus closed, handle sections 42 and 46 are bent upwardly about the score lines 39 so as to extend into proximity with each other adjacent their outer ends, in position to be grasped together by the hand for carrying the carton, as shown in Figs. 3 and 4. It will be noted that the handle sections are connected with their closure flaps along the score lines 38 at locations. intermediate and substantially midway between the center of the closure and the adjacent corners of the carton, preferably slightly nearer the carton corners, as shown, so that in lifting the carton by the handles, the weight is transmitted to the closure flaps between the locking means at the carton center and the carton comers.

This arrangement has been found to have several advantages. It transmits the weight of the carton to the wide, uncut bases of the flaps 31 and 38 at which they are best adapted to support such weight. The connection of the handles at this location intermediate the interlocked parts and the side walls, also affords a resilient type of connection with sufiicient spring to absorb jars and shocks in transportation and reduce the tendency to tear the material. It will also be seen that the weight of the carton is transmitted to the closure flaps and handles as stresses of the substantially tensile character such as the cardboard is best adapted to sustain. By cutting the blank from the cardboard stock so that the grain of the stock extends from the base toward the outer free ends of the flaps 31 and 38, any tendency of the handle sections to tear is diminished and directed toward the carton corners at the base of the flaps, so as to avoid detachment of the handles.

The interlocking parts 43 and 45 are at the outer ends of locking sections 4| and 44, which extend at a substantial distance outwardly beyond their folding score lines 39, to provide free tongue portions of sufficient length to facilitate ready manipulation of the locking parts into engagement with each other. At the same time, the locking sections remain connected with the handle sections for a substantial distance from the base of the flaps so as to maintain alinement and avoid separation of the locking and handle sections of each flap, during manipulation in the machine by which the folding and erection of the cartons is accomplished.

The locking sections are separated from the associated handle sections by cuts 40 of such shape as to produce ample openings in the handles for receiving the fingers, and the handles, as well as the locking sections, are formed in those flaps extending integrally from the sides of the carton which are reinforced and stiffened by the corner flaps, so as to obtain maximum strength for the sections and preserve the rigidity of the carton.

It will be apparent from the above construction and description that the pail is adapted to maintain its shape while being filled. Its top opening may be quickly and easily closed and the locking parts interengaged by the simple operation of pushing them together which may be readily accomplished by unskilled operators. When locked, the top flaps serve to maintain a substantially leak-proof closure, in keeping with the liquid-tight construction of the body of the pail. The handle sections are extended from the reinforced side walls of the pail, at points intermediate the top corners of such sides and the central closure locking means, so as to provide a resilient, or spring connection with the carton, with the imposed stresses of a substantially tensile nature having the least tendency to tear the material. Handles so constructed have been found to have several times the strength of integral cardboard handles such as heretofore used in this art. Such advantages are accomplished in a; construction which obviates any separately formed attachments of wire or other metallic or expensive materials, either for locking the closure flaps or providing carrying handles, as well as additional operations for attaching the same, or any additional amount of cardboard stock.

While the invention is herein disclosed by a detailed description of a preferred form of embodiment, it is to be understood that this disclosure is intended. to be illustrative, rather than limiting, as it is contemplated that various changes in the construction and arrangement of the parts will occur to those skilled in the art,

within the spirit of the invention and the scope of the appended claims.

I claim:

1. A leak-proof carton made from a single sheet of material cut, scored and folded to form a bottom and four tapered side walls folded integraliy upwardly from said bottom with folded corner portions integrally connecting adjacent side walls, said corner portions being folded outwardly and secured in overlapping pairs against a first pair of opposite side walls, the other pair of opposite side walls having flaps at their tops folded inwardly to form inner top closure flaps, said first pair of side walls having outer flaps at their tops folded inwardly and upwardly at the respective corners of the carton to hold said inner flaps closed and stiffen said first pair of side walls, each of said outer flaps having a scored fold line extending thereacross parallel with said carton corner intermediate the same and the center of the carton closure and having a cut extending outwardly from said fold line and separating said flap into an inner locking section and an outer handle section, one of said locking sections having an elongated eye out interiorly therein and transversely thereof and the other section having a beveled and formed oppositely with shoulders extending transversely thereof for insertion in and interlocking engagement with the opposite ends of said eye, said locking sections having free flexible portions of substantial length adapted to be bent inwardly and downwardly about said fold line and interlocked with one another by inward and downward pressure thereon, and said handle sections being folded obliquely upwardly about said fold line to resiliently support the carton weight by a substantial tensile pull on said-sheet material.

2. A leak-proof carton made from a single sheet of material cut, scored and folded to form a bottom and four tapered side walls folded integrally upwardly from said bottom with folded corner portions integrally connecting adjacent side walls, said corner portions at two opposite corners being folded outwardly and secured by spots of glue located in the upper central portions of a first pair of opposite'side walls, the remaining corner portions being folded outwardly and glued to the first mentioned pair of corner portions, the other pair of opposite'side walls having flaps at their tops folded inwardly to form inner top closure flaps, said first pair of side walls having outer flaps at their tops folded inwardly and upwardly at the respective corners of the carton to hold said inner flaps closed and stiffen said first pair of side walls, each of said outer flaps having a scored fold line extending thereacross parallel with said carton corner intermediate the same and the center of the carton closure and having a cut extending outwardly from said fold line and separating said flap into an inner locking section and an outer handle section, one of said locking sections having an elongated eye out interiorly therein and transversely thereof and the other section having a beveled end formed oppositely with shoulders extending transversely thereof for insertion in and interlocking engagement with the opposite ends of said eye, said locking sections having free flexible portions of substantial length adapted to be bent inwardly and downwardly about said fold line and interlocked with each other by inward and downward pressure thereon, and said handle sections being folded obliquely upwardly about said fold line to resiliently support the carton weight by a substantial tensile pull on said sheet material.

WILLIAM H. INMAN. 

